When facing high pollution load influent, what pretreatment measures does the ultrafiltration pure water equipment take to protect the membrane components and extend their life?
Publish Time: 2025-04-24
When dealing with high pollution load influent, the main challenge faced by the ultrafiltration pure water equipment is how to effectively remove large particle impurities, suspended matter, organic matter and possible microorganisms in the water to protect the membrane components from damage and extend their service life. In order to meet these challenges, ultrafiltration systems usually integrate a series of pretreatment measures to ensure that the water quality entering the ultrafiltration membrane meets the requirements, thereby maintaining the efficient operation and stable output of the system.
First, grid filtration is the first step in pretreatment. By installing grids of different coarseness and fineness, larger solid particles such as branches, leaves, plastic fragments, etc. can be effectively intercepted to prevent them from entering the subsequent treatment unit and causing blockage or damage. The design of the grid needs to be selected according to the specific water source conditions. For water sources containing more large debris, a denser grid arrangement can significantly improve the interception effect and reduce the pressure of subsequent treatment steps.
Then, the sedimentation tank or clarifier is used to further remove suspended particles in the water. Using gravity, heavier particulate matter will naturally settle to the bottom of the pool to form a sludge layer, while the supernatant is relatively clear, which can reduce the burden on the ultrafiltration membrane. The precipitation process can be enhanced by adding chemical agents (such as flocculants) to promote the aggregation of tiny particles into larger agglomerates for easy sedimentation and separation. This method not only improves the efficiency of solid-liquid separation, but also effectively reduces the content of colloids in water, providing a cleaner water source for ultrafiltration.
Sand filtration is also one of the common pretreatment processes. After preliminary precipitation, the water flows through a filter bed composed of multiple layers of quartz sand or other filter media with different particle sizes to further remove residual small particle impurities. Sand filtration can not only intercept physical pollutants, but also has a certain biological purification ability. Under appropriate conditions, it can cultivate beneficial microbial communities to help decompose some organic pollutants. In addition, regular backwashing operations can restore the filtration performance of the sand filter layer and ensure long-term stable operation.
Activated carbon adsorption technology is also indispensable. Activated carbon has a huge specific surface area and rich pore structure, which can strongly adsorb organic matter, odor molecules and certain heavy metal ions in water. Activated carbon plays a particularly important role in treating surface water with high concentrations of volatile organic compounds (VOCs) or darker colors. It not only improves the sensory properties of water quality, but also reduces the pressure on ultrafiltration membranes facing complex organic pollutants and avoids the decrease in flux caused by clogging of membrane pores.
For water sources with a high risk of microbial contamination, disinfection pretreatment is particularly important. Common disinfection methods include chlorination disinfection, ozone oxidation, and ultraviolet irradiation. Chlorination disinfection kills most bacteria and viruses by adding an appropriate amount of sodium hypochlorite or chlorine to the water; ozone, as a strong oxidant, can efficiently kill microorganisms in a short time without producing persistent disinfection by-products; ultraviolet irradiation is based on the principle that ultraviolet light destroys the DNA structure of microorganisms to achieve rapid sterilization. These disinfection measures can greatly reduce the possibility of biological contamination of ultrafiltration membranes and extend the cleaning cycle and service life of the membrane.
Finally, pH adjustment is also an important link that cannot be ignored. The pH value of many natural water sources is not ideal. Too high or too low may cause chemical reactions on the membrane surface, affecting the performance of the membrane and even causing irreversible damage. Therefore, before entering the ultrafiltration stage, it is helpful to properly adjust the pH value of the influent to an appropriate range (usually 6.5-7.5) to help maintain the membrane in good condition. This step can be achieved by adding acid and alkali reagents, and at the same time, the online monitoring system can monitor the pH changes in real time to ensure that the treatment process is always under optimal control.
In summary, when facing high-pollution-load influent, ultrafiltration pure water equipment uses a series of carefully designed pretreatment measures, from physical filtration to chemical purification to biological control, to fully protect the ultrafiltration membrane components and ensure the efficient and stable operation of the entire system. These pretreatment methods not only improve the final water quality, but also greatly extend the service life of the membrane, reduce operating costs, and bring significant economic and environmental benefits to enterprises and society. With the advancement of science and technology, more innovative technologies and intelligent management systems will be applied to this field in the future, promoting ultrafiltration pure water equipment to develop in a more intelligent and efficient direction.
